| Overview |  |
color_name() = ecaptcha_color:color_name()
color_rgb() = ecaptcha_color:rgb()
err_reason() = chars_not_binary | wrong_chars_length | invalid_character | bad_random | small_rand_binary | opts_not_list | non_atom_option | unknown_option
opts() = [line | blur | filter | dots | reverse_dots]
line - draws a curved horisontal line on top of the text
blur - blurs the image (averages each pixel's color with it's neighbours)
filter - makes letters hollow
dots - draws 100 random 2x2 white dots on top of the image, effectively removing small pathes
from it
reverse_dots - draws 20 random dots of a randomized size from 1 to 3px using a color opposite
to the current color (so, reversing the color - black becomes white, white becomes black)
| gif/3 | Generate GIF image 200x70 with NumChars letters on it. |
| pixels/2 | Generate greyscale array of pixels 200x70. |
| png/3 | Generate PNG image 200x70 with NumChars letters on it. |
gif(NumChars::pos_integer(), Opts::opts(), Color::color_name() | color_rgb()) -> {Str::binary(), GifImg::binary()} | {error, err_reason()}
Generate GIF image 200x70 with NumChars letters on it
Same aspng/3, but image is in GIF format.
pixels(NumChars::pos_integer(), Opts::opts()) -> {Str::binary(), Pixels::binary()} | {error, err_reason()}
NumChars: how many characters should be on a image, 1..6
Opts: list of additional effects to apply to the image
Generate greyscale array of pixels 200x70
It returns a tuple where 1st element is a binary ASCII string which contains characters that are printed on captcha image. 2nd element is a plain binary that contains 200x70 = 14000 "pixels", 1 byte each, where 0 means black and 255 - white, intermediate values are shades of grey.png(NumChars::pos_integer(), Opts::opts(), Color::color_name() | color_rgb()) -> {Str::binary(), PngImg::binary()} | {error, err_reason()}
NumChars: - same as in pixels/2
Opts: - same as in pixels/2
Color: - use shades of this color instead of shades of grey. Can be one from the set of
recommended named colors or {Red, Green, Blue} RGB tuple
Generate PNG image 200x70 with NumChars letters on it
It returns a 2-tuple where 1st element is the binary containing ofNumChars size containing
ASCII string that is printed on the image and 2nd element is PNG-encoded image that can be, eg
sent directly to the browser with Content-Type: image/png.
Generated by EDoc